What is the role of plasma in the blood?

Plasma plays a crucial role in the blood primarily by carrying nutrients and waste products throughout the body. It is the liquid portion of blood, constituting about 55% of its volume. Plasma contains various components, including water, electrolytes, proteins, hormones, and waste materials. It serves as a medium through which nutrients from digested food are transported to the cells and tissues that need them for energy and growth. Additionally, plasma carries metabolic waste products, such as urea and carbon dioxide, away from cells to be excreted from the body.

While clotting is an important function related to specific proteins found in plasma, and immune responses involve components of plasma, these processes are secondary roles. The transport of oxygen is primarily the function of red blood cells, not plasma. Therefore, the primary role of plasma remains the transportation of nutrients and waste, emphasizing its essential function in maintaining overall body homeostasis.